Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak

H. Tanabe, T. Yamada, T. Watanabe, K. Gi, K. Kadowaki, M. Inomoto, R. Imazawa, M. Gryaznevich, C. Michael, B. Crowley, N. J. Conway, R. Scannell, J. Harrison, I. Fitzgerald, A. Meakins, N. Hawkes, K. G. McClements, T. O'Gorman, C. Z. Cheng, Y. Ono

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Electron and ion heating characteristics during merging reconnection start-up on the MAST spherical tokamak have been revealed in detail using a 130 channel yttrium aluminum garnet (YAG) and a 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron density have been achieved for the first time and it is found that electron temperature forms a highly localized hot spot at the X point and ion temperature globally increases downstream. For the push merging experiment when the guide field is more than 3 times the reconnecting field, a thick layer of a closed flux surface form by the reconnected field sustains the temperature profile for longer than the electron and ion energy relaxation time ∼4-10 ms, both characteristic profiles finally forming a triple peak structure at the X point and downstream. An increase in the toroidal guide field results in a more peaked electron temperature profile at the X point, and also produces higher ion temperatures at this point, but the ion temperature profile in the downstream region is unaffected.

Original languageEnglish
Article number215004
JournalPhysical Review Letters
Volume115
Issue number21
DOIs
Publication statusPublished - Nov 18 2015

Fingerprint

ion temperature
temperature profiles
electron energy
heating
ions
electrons
ruby
Thomson scattering
profiles
yttrium-aluminum garnet
tomography
relaxation time
temperature
energy

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak. / Tanabe, H.; Yamada, T.; Watanabe, T.; Gi, K.; Kadowaki, K.; Inomoto, M.; Imazawa, R.; Gryaznevich, M.; Michael, C.; Crowley, B.; Conway, N. J.; Scannell, R.; Harrison, J.; Fitzgerald, I.; Meakins, A.; Hawkes, N.; McClements, K. G.; O'Gorman, T.; Cheng, C. Z.; Ono, Y.

In: Physical Review Letters, Vol. 115, No. 21, 215004, 18.11.2015.

Research output: Contribution to journalArticle

Tanabe, H, Yamada, T, Watanabe, T, Gi, K, Kadowaki, K, Inomoto, M, Imazawa, R, Gryaznevich, M, Michael, C, Crowley, B, Conway, NJ, Scannell, R, Harrison, J, Fitzgerald, I, Meakins, A, Hawkes, N, McClements, KG, O'Gorman, T, Cheng, CZ & Ono, Y 2015, 'Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak', Physical Review Letters, vol. 115, no. 21, 215004. https://doi.org/10.1103/PhysRevLett.115.215004
Tanabe, H. ; Yamada, T. ; Watanabe, T. ; Gi, K. ; Kadowaki, K. ; Inomoto, M. ; Imazawa, R. ; Gryaznevich, M. ; Michael, C. ; Crowley, B. ; Conway, N. J. ; Scannell, R. ; Harrison, J. ; Fitzgerald, I. ; Meakins, A. ; Hawkes, N. ; McClements, K. G. ; O'Gorman, T. ; Cheng, C. Z. ; Ono, Y. / Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak. In: Physical Review Letters. 2015 ; Vol. 115, No. 21.
@article{a5a92ae0de4449d38be0a077400817d0,
title = "Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak",
abstract = "Electron and ion heating characteristics during merging reconnection start-up on the MAST spherical tokamak have been revealed in detail using a 130 channel yttrium aluminum garnet (YAG) and a 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron density have been achieved for the first time and it is found that electron temperature forms a highly localized hot spot at the X point and ion temperature globally increases downstream. For the push merging experiment when the guide field is more than 3 times the reconnecting field, a thick layer of a closed flux surface form by the reconnected field sustains the temperature profile for longer than the electron and ion energy relaxation time ∼4-10 ms, both characteristic profiles finally forming a triple peak structure at the X point and downstream. An increase in the toroidal guide field results in a more peaked electron temperature profile at the X point, and also produces higher ion temperatures at this point, but the ion temperature profile in the downstream region is unaffected.",
author = "H. Tanabe and T. Yamada and T. Watanabe and K. Gi and K. Kadowaki and M. Inomoto and R. Imazawa and M. Gryaznevich and C. Michael and B. Crowley and Conway, {N. J.} and R. Scannell and J. Harrison and I. Fitzgerald and A. Meakins and N. Hawkes and McClements, {K. G.} and T. O'Gorman and Cheng, {C. Z.} and Y. Ono",
year = "2015",
month = "11",
day = "18",
doi = "10.1103/PhysRevLett.115.215004",
language = "English",
volume = "115",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "21",

}

TY - JOUR

T1 - Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak

AU - Tanabe, H.

AU - Yamada, T.

AU - Watanabe, T.

AU - Gi, K.

AU - Kadowaki, K.

AU - Inomoto, M.

AU - Imazawa, R.

AU - Gryaznevich, M.

AU - Michael, C.

AU - Crowley, B.

AU - Conway, N. J.

AU - Scannell, R.

AU - Harrison, J.

AU - Fitzgerald, I.

AU - Meakins, A.

AU - Hawkes, N.

AU - McClements, K. G.

AU - O'Gorman, T.

AU - Cheng, C. Z.

AU - Ono, Y.

PY - 2015/11/18

Y1 - 2015/11/18

N2 - Electron and ion heating characteristics during merging reconnection start-up on the MAST spherical tokamak have been revealed in detail using a 130 channel yttrium aluminum garnet (YAG) and a 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron density have been achieved for the first time and it is found that electron temperature forms a highly localized hot spot at the X point and ion temperature globally increases downstream. For the push merging experiment when the guide field is more than 3 times the reconnecting field, a thick layer of a closed flux surface form by the reconnected field sustains the temperature profile for longer than the electron and ion energy relaxation time ∼4-10 ms, both characteristic profiles finally forming a triple peak structure at the X point and downstream. An increase in the toroidal guide field results in a more peaked electron temperature profile at the X point, and also produces higher ion temperatures at this point, but the ion temperature profile in the downstream region is unaffected.

AB - Electron and ion heating characteristics during merging reconnection start-up on the MAST spherical tokamak have been revealed in detail using a 130 channel yttrium aluminum garnet (YAG) and a 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron density have been achieved for the first time and it is found that electron temperature forms a highly localized hot spot at the X point and ion temperature globally increases downstream. For the push merging experiment when the guide field is more than 3 times the reconnecting field, a thick layer of a closed flux surface form by the reconnected field sustains the temperature profile for longer than the electron and ion energy relaxation time ∼4-10 ms, both characteristic profiles finally forming a triple peak structure at the X point and downstream. An increase in the toroidal guide field results in a more peaked electron temperature profile at the X point, and also produces higher ion temperatures at this point, but the ion temperature profile in the downstream region is unaffected.

UR - http://www.scopus.com/inward/record.url?scp=84948411419&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84948411419&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.115.215004

DO - 10.1103/PhysRevLett.115.215004

M3 - Article

AN - SCOPUS:84948411419

VL - 115

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 21

M1 - 215004

ER -